The present invention relates to a seat frame and a vehicle seat, particularly to a seat frame for reducing an input load to a reclining mechanism at the time of rear surface collision, and a vehicle seat.
Conventionally, when a motor vehicle is collided at its rear part or collides when backing up, so called at the time of rear surface collision, a seated passenger is sometimes radically moved rearward due to inertia and pushed onto a backrest front surface of a seat back. Accordingly, there is a fear that an excessive input load is provided to a reclining mechanism for adjusting a reclining angle of the seat back.
In order to prevent such an excessive input load to the reclining mechanism, as shown in FIG. 5, a notch 100 is formed in a lower side part of a seat back frame 111 in a seat frame for a vehicle seat of a motor vehicle or the like. At the time of the rear surface collision, a seat back (the seat back frame 111) can fall downward from a part where this notch 100 is formed. Thus, the excessive load above a limit provided to a reclining mechanism 120 is prevented (for example, refer to Japanese Patent Application Publication No. 2003-335162 (“the '162 Publication”), and Japanese Patent Application Publication No. 2006-347436 (“the '436 Publication”)).